
int main(int argc, char* argv[])
{
	int i, j, n, t, flag;
	char syx[21];
	scanf("%d", &n);
	for (i=0; i<n; i++)
	{
		flag = 1;
		scanf("%s", syx);
		t = strlen(syx);
		for (j=0; j<t; j++)
		{
			if(syx[j]==95)
				continue;
			else if(j==0 && syx[j] < 65 || syx[j] > 90 && syx[j] < 94 || syx[j] > 96 && syx[j] < 97 || syx[j]>122)
			{
				flag = 0;
				break;
			}
			else if(syx[j] < 48 || syx[j]>57 && syx[j] < 65 || syx[j] > 90 && syx[j] <97 || syx[j] > 122)
			{
				flag = 0;
				break;
			}
		}
		if (flag == 0)
			printf("no\n");
		else
			printf("yes\n");
	}

	return 0;
}